In the semiconductor manufacturing technology, the mechanism of the lithograph process is that copying temporary circuit configurations onto a wafer to be performed an etching and an ions implantation. Photosensitive photoresist material and controllable exposure ware are used to form three-dimensional patterns on the wafer surface. The photosensitive photoresist material or the photoresist material applied to the lithograph process, as a polymerized dissoluble compound, is coated on the wafer surface and patterned, then removed after the etching or the ions implantation. Therefore, the thickness and the uniformity of the photoresist material coated on the wafer surface are key parameters to measure the coating quality.
In the semiconductor manufacturing industry, the factors causing abnormal photoresist coating exist widely, majority of which are caused by the machine failure. However, one of the factors caused by the structure of the photoresist bottle, often occurs and cannot be solved by the machine maintenance.
Referring to FIG. 1, which is a schematic view illustrating a photoresist bottle according to the prior art. As shown in the FIG. 1, the prior photoresist bottle usually adopts the NOWPak packaging, which comprises an inner liner and an external shell. Wherein, the external shell is a photoresist bottle body 1 having a connector 5, and the inner liner is a soft liner 2 used to fill with the photoresist 3, the photoresist 3 is out of touch with the outer air and the bottle body 1. A nitrogen gas tube 6 is inserted into the interspace between the bottle body 1 and the soft liner 2 through the connector 5. A photoresist conduit 4 is inserted into the bottom of the soft liner 2 through the connector 5. A hose 7 is connected to the upper end of the photoresist conduit 4 in the connector 5. Due to the photoresist bottle has been sealed, when the nitrogen gas is introduced through the nitrogen gas tube 6 by the high pressure to press the soft liner 2, the photoresist 3 is extruded out through the photoresist conduit 4, and guided to the machine via the hose 7. Referring to FIG. 2, which is a fragmentary enlarged schematic view illustrating the photoresist conduit in the FIG. 1. As shown in the FIG. 2, the lower end 8 of the photoresist conduit 4 is cone shaped, of which sidewall arranges a photoresist outlet 9.
During the photoresist is extruded out through the photoresist conduit 4, the photoresist outlet 9 is usually blocked by the deformed soft liner 2 under the combined effect of the pressing of the nitrogen gas outside the soft liner and the suction of the photoresist outlet 9 inside the soft liner. The blocked photoresist outlet 9 will alter the pressure of the subsequent photoresist pipeline, cause the emergence of a large number of bubbles therein, and further more badly cause the abnormal coating due to the insufficient of the photoresist during the coating process.
The above-mentioned case will happen more easily when the photoresist will be run out. As shown in the FIG. 3, the soft liner 2 is gradually close to the photoresist conduit 4 when the photoresist therein will be run out. The photoresist 3 in the top of the soft liner not only is difficult to flow smoothly to the photoresist outlet 9 positioned at the lower end of the photoresist conduit 4, but also is easier to block the photoresist outlet 9.
Therefore, it is necessary to perform a structure optimization for the prior photoresist bottle, in order to solve the poor coverage problem of coating.